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I'm curious as to why people keep saying open center. I know of no instance where an open center is of any use at all.

I don't know either. It very clearly says in the manual the center is a viscous LSD with a "hump-mode" where the plates couple if the center overheats and the diff, for all intents and purposes, locks. There's even an awesome torque coupling vs. heat (or load) graph!

And the rear for the 05-09 LGT is the standard viscous LSD, the front is open. I tested this a few weeks back in the snow storm and mine still works. O

Viscous is just about as useless as an open differential. It's torque transfer very very low, so low it won't actually make any noticeable difference. It uses the heat from slip to increase the viscosity (thickness) of the fluid, which in theory the thicker fluid will force torque transfer. There are a few problems with this - you need to be spinning the wheel pretty aggressively to heat up the fluid and force the torque transfer - and once the fluid heats up, the amount of torque it can send is still very very low.

Except that you're missing the point where the VLSD locks up as the sheer forces increase temperature. The sheer thickening fluid transfer is what transfers the torque (heat independent), and the heat generated induces lockup. Infact, fluid only serves to provide smooth lockup, it's mostly the plates acting in a clutch-like fashion that do the torque transfer if needed. As subaru states, the hump phenomenon serves to eliminate the rotational difference between the housing and the hub, directly coupling the front and rear axles.